In high-frequency communication, especially on a millimeter-wave band, an attenuation degree of a transmit signal is far greater than that at a lower frequency (6 gigahertz (GHz)). To reduce attenuation of a high-frequency signal, the signal is usually sent using beams. When beam bandwidth is sufficiently narrow, a transmit end and a receive end can reach a specific communication distance and transmission rate. However, when the beam is excessively narrow, it is very difficult for the transmit end and the receive end to discover each other, and when the beam is excessively wide, an antenna gain is not high, and an ideal transmission rate cannot be obtained. Therefore, in the Institute of Electrical and Electronics Engineers (IEEE) 802.11ad standard, Sector Level Sweep (SLS) is designed to implement device discovery and sector level beam sweep, and a beam refinement protocol (BRP) is designed to optimize a receive beam and a transmit beam. According to stipulations in the BRP, both a receiving party and a sending party can implement beam training and beam tracking by sending a BRP packet. IEEE 802.11ad supports only transmission on a single antenna (single radio frequency channel) on a single 2.16 GHz channel. To improve a throughput of a wireless local area network (WLAN), support of a channel bonding (CB) technology and a Multiple-Input Multiple-Output (MIMO) technology in an IEEE 802.11ad based framework is currently under discussion in IEEE 802.11ay. However, in a current BRP, a BRP packet is designed for a case in which a single 2.16 GHz channel is supported. Therefore, there is no definite solution to how the transmit end sends the BRP packet on a plurality of channels.